NATO also recognises several different types of fire support for tactical purposes:
- Counterbattery fire: delivered for the purpose of destroying or neutralizing the enemy's fire support system.
- Counterpreparation fire: intensive prearranged fire delivered when the imminence of the enemy attack is discovered.
- Covering fire: used to protect troops when they are within range of enemy small arms.
- Defensive fire: delivered by supporting units to assist and protect a unit engaged in a defensive action.
- Final Protective Fire: an immediately available prearranged barrier of fire designed to impede enemy movement across defensive lines or areas.
- Harassing fire: a random number of shells are fired at random intervals, without any pattern to it that the enemy can predict. This process is designed to hinder enemy forces' movement, and, by the constantly imposed stress, threat of losses and inability of enemy forces to relax or sleep, lowers their morale.
- Interdiction fire: placed on an area or point to prevent the enemy from using the area or point.
- Preparation fire: delivered before an attack to weaken the enemy position.
These purposes have existed for most of the 20th century, although their definitions have evolved and will continue to do so, lack of suppression
is an omission. Broadly they can be defined as either:
- Deep supporting fire: directed at objectives not in the immediate vicinity of own force, for neutralizing or destroying enemy reserves and weapons, and interfering with enemy command, supply, communications and observation; or
- Close supporting fire: placed on enemy troops, weapons or positions which, because of their proximity present the most immediate and serious threat to the supported unit.
Two other NATO terms also need definition:
- Neutralization fire: delivered to render a target temporarily ineffective or unusable; and
- Suppression fire: that degrades the performance of a target below the level needed to fulfill its mission. Suppression is usually only effective for the duration of the fire.